Connect to SVE or other OPC server failed by server explorer

[alex.]

I am tring to setup a OPC client to connect to a OPC server on another PC.

The 2 OPC servers I tried to connected to is the SVE engine and the ICCP server.

But I cannot even find any OPC server in the view list.

When I create a OPC client, I use 2 ways. One is to use the server explorer, another is to create a new OPC server binding to a source, but all cannot find the source.

[MattP]

Hello,

Depending on what operating system you are using, there are often additional steps required to allow OPC clients on a remote machine to access OPC servers running on a second machine.  This is because Windows has built-in Distributed COM security settings that prevent OPC communication from happening smoothly until these settings are modified.  If you haven't already, you should take a look at a document on the OPC Foundation's website about using OPC via DCOM on Windows XP.  It describes some of the procedures necessary to allow this kind of communication to happen.

I also suggest verifying that the OPC server is working correctly by connecting to it via an OPC client on the same machine as the server, and to verify that you are logged in with administrative priveleges, as OPC can be sensitive to user priveleges.  If after going through the document above you still have questions, I'll need to know what operating system you're using on both the client and server machines and if an OPC client running on the same machine as the server works correctly to best advise you as to the next steps to take.

[alex.]

I follow the article and open all the control settings on booth sides, but still cannot connect to the server.

But using the same pc as server and client, then can connected.

Any suggestion?

[Craig_D]

turbot,

Can you ping the server computer from the client computer?  Pinging shows if communication is even possible between these computers.

Do you have a firewall or antivirus software running which may be blocking communications?  If you disable these, what happens?

Remote OPC uses a program called opcenum.exe which scans the registry and returns a list of OPC servers available on the server computer that can be browsed from the client computer via DCOM.  If opcenum.exe were terminated for some reason, that would explain the inability to browse on the client computer.

If you press ctrl+shift+esc on the server computer, do you see opcenum.exe as a running process?  If you go into control panel»administrative tools»services, do you see OpcEnum as "started"?

Regards,

Craig D

Applications Engineer

National Instruments

[alex.]

Can ping to the server,

After I add the logon for RPC window service, it can link but give error message as attached.

There is no windows services called OpcEnum, but see opcenum.exe running on client side.

[MattP]

Obtaining a list of available OPC servers available on the remote machine is possible without the OPCEnum service running, though setting up a connection to it via LabVIEW DSC can run into exactly the type of problem that you are seeing.  I recommend installing the OPC Foundation's basic set of OPC services (which are installed by most OPC Server packages on the market) - this set of services includes OPCEnum as a primary component.  You can find an installer for these services on your DSC CD, located in the Products\OPC_Support\opcsupp.msi directory.  Run opcsupp.msi on your server computer and restart - you should now have opcenum.exe listed in your set of running processes when you try to connect to it from your client machine.  Please give this a try, and let us know if you run into any troubles!

[alex.]

Thanks, after install the OPC core component 2.0, it can link up.

[MattP]

Great!  I'm glad to hear it's working now - let me know if you run into any more troubles with it!

[alex.]

Now come to the link below,

http://forums.ni.com/ni/board/message?board.id=170&message.id=292871&jump=true